China Solenoid

Contrary to an alternating current (AC) solenoid, the power consumption of a direct current (DC) solenoid is independent of the position of the plunger. DC solenoids are also characterised by soft and hard operation. Inherently longer cycling times can be reduced by special circuitry. It is also possible to modify the stroke-force characteristics. High switching frequencies do not cause dangerously high thermal loads in DC solenoids; the maximum switching frequency is only limited by the pull-in and drop-out times.

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A solenoid is a device designed to convert electrical energy into linear work: this can be either push or pull.

The moving part of the solenoid is called the plunger and it is the movement of the plunger which is expressed as the stroke, measured in millimetres.

To select a solenoid for a given application, it is necessary for the user to answer the following questions:

• What is the linear movement needed?
• How much force is required to perform the operation?
• What is the space limitation for the solenoid?
• What is the duty cycle of the solenoid?
• What is the operating temperature range?
• Are there any special industrial environmental concerns?
• Is there need for additional circuit protection?
• What size lead wire and length of lead is required?

Magnetic Field of a Solenoid

Magnetic fields are produced by electric currents; a simple segment of current-carrying wire will generate around it a circular magnetic field in accordance with the right hand rule.

You can create a stronger magnetic field by taking wire and forming it into a coil; the field is more concentrated in the center of the loop than outside the loop. By adding more loops to a coil, you create an increasingly stronger magnetic field. Stacking multiple loops also concentrates the field even more; this arrangement is known as a solenoid

A solenoid is a coil of insulated or enameled wire wound on a rod-shaped form made of solid iron, solid steel, or powdered iron. Devices of this kind can be used as electromagnets, as inductors in electronic circuits, and as miniature wireless receiving antennas....